1. Field of the Invention
This invention relates to a dispenser for paste-like materials. The dispenser has multiple seals and an integrated cover which automatically open when material is being dispensed and automatically close when material is not being dispensed. Various embodiments include a removable cartridge for replenishing material and a movable applicator.
2. Description of Related Art
In recent years toothpaste pumps have been widely accepted by consumers as a convenient way for dispensing toothpaste. Pump dispensers have also been used for dispensing other viscous materials such as cosmetic creams, lotions and the like. Consumer preference for using pump dispensers rather than tube type dispensers is at least partially attributable to the pump's rigid shape, its ability to stand upright on a surface and the ease with which the remaining or residual contents are removed when the dispenser is in a near empty state. Notwithstanding these advantages, pump dispensers are more expensive to fabricate than tube type dispensers and are not reusable. Moreover, many pump dispensers have more than one sealing cap which must be manually replaced after each use for hygienic purposes as well as to prevent toothpaste from becoming dried out by ambient air and thereby clogging the dispenser's spout.
A variety of pump dispensers are described in the prior art. Several improvements have recently been made in the design and fabrication of such dispensers. U.S. Pat. No. 4,511,068 as well as U.S. Pat. Nos. 4,538,747 and 4,485,943 describe toothpaste pumps which are more economical to fabricate than comparative prior art devices. The cost for producing the pumps described in these patents is still much greater than the manufacturing cost for tube type dispensers. Moreover, the patented dispensers are not reusable and must be discarded when the contents are depleted. Other patents, such as U.S. Pat. No. 4,394,939, U.S. Pat. No. 4,402,431 and Reissue No. 31,408, disclose improvements in controlling the quantity of material discharged. While these patents describe dispensers which more efficiently control each dose of discharged material as compared to other prior art devices, the number and arrangement of parts required to accomplish this purpose adds to the fabrication costs. This same consideration applies to U.S. Pat. No. 4,565,306 which discloses a pump that is capable of more rapidly discharging toothpaste than other available dispensers.
Each of the dispensers described in the referenced patents recognizes that the dispensers must be carefully sealed when not in use to prevent unwanted caking of dried material which clogs the discharge spout. In most cases, two seals are used to ensure that the spout is not exposed to ambient air when the dispenser is not in use. Typically, a plug is placed in the spout and a cover is placed over the spout after each use to protect the material from the ambient air. This poses an inconvenience to the user since the cover and plug must be separately, manually removed and replaced after each use. Thus, the prevention of clogging and the continued efficiency of the dispenser are dependent on the user manually replacing the plug and cap after each use.
Certain brands of toothpaste are marketed in a dispenser which has a flap for sealing the spout instead of a plug. In this type of dispenser, the flap is attached to a handle which actuates the pump in a manner such that the flap is removed from the spout when a pumping pressure is applied to the handle. Because the flap does not efficiently provide an air tight seal, the dispenser also contains a cover to protect the spout from ambient air. The cover must be manually removed prior to pumping and unsealing. In this type of dispenser, material is pumped when the spout is partially opened which at times causes the formation of residual material around the spout. Despite the use of a sealing flap, possible clogging or caking is prevented or reduced only by the additional step of manually repositioning the removable cover after each use.
The objects of the present invention are to provide a dispenser for paste-like materials wherein the dispenser's spout is automatically sealed and covered after each use; to provide a reusable dispenser which is economically more efficient on a cost per use basis than other comparative dispensers because of its reusability; to provide a dispenser which discharges a controlled quantity of material during each application; and to provide a dispenser which has a movable spout for increased accessibility and for distribution of a length of material over a stationary surface.